312 



MEDUS.E of the world. 



these are not found at the sides of the larger tentacles. Each tentacle-bulb bears an abaxial 

 excretion papilla. The thread-like lash of each tentacle is ringed by numerous nematocyst- 

 ridges, but has not the longitudinal muscle strand seen in Tima. There are about too small, 

 vesicular lithocysts, each containing 2 to 4 concretions. The velum is very narrow. 



The peduncle is half as long as the bell-radius. It is pyramidal, slender, and half as wide 



at its base as long. It is much smaller and 

 more slender than the peduncle oi Tima 

 pellucida with which this medusa has at 

 times been confused. The stomach is about 

 a third as long as the gelatinous peduncle 

 and there are 4 long, lanceolate lips with 

 crumpled margins. The 4 radial-canals are 

 very slender. They extend straight down 

 the perradial sides of the peduncle, but are 

 slightly wavy over the subumbrella. The 

 ring-canal is narrow and simple. The 4 

 linear, somewhat sinuous gonads are devel- 

 oped upon the subumbrella portions ot the 

 4 radial-canals from near the base of the 

 peduncle to near the circular vessel. 



The tentacles, gonads, and stomach 

 are milky-white, green, or reddish. 



This medusa is found off the Atlantic 

 coasts of Europe from Helgoland to the 

 Mediterranean. It is occasionally found 

 at Naples, on the surface. 



The dimensions of a large specimen in 

 Dr. Lobianco's collection at Naples are as 

 follows: Bell 48.5 mm. wide; peduncle 12 

 mm. long, and 6 mm. wide at its base; 

 stomach 4 mm. long; long tentacles 5 mm. 

 long; short tentacles 2 or 3 mm. long. 

 The hydroid is unknown. Bigelow, and 

 also Torrey, 1909, find a closely allied 



Fig. lji.—Eirene viridula. Drawn by the author from a medusa with broader peduncle, SOUthweSt 

 specimen collected by Dr. Lobianco in the Bay of Naples. rf R G 1 Islands, tropical Pacific, 



Oral view of medusa. Enlarged view of part of the V-,- /~i -r • 



bell-margin. and at San Diego, California. 



Eirene variabilis. 

 Plate 38, fig. 4; plate 39, fig. 1. 



F.uiima variabilis, McCradv, 18C7, Gymn. Charleston Harbor, p. 88. — Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 363. — 

 Agassiz, A., 1865, North Amer. Acal., p. 116. — Brooks, 1886, Mem. Boston Soc. Nat. Hist., vol. 3, p. 396, plate 39, 

 fig. 1 ; plate 40, fig. I. 



Octorchandra variabilis, Haeckel, 1879, Syst. der Medusen, p. 199. 



Adult medusa. — Bell about 30 mm. in diameter and about 3 times as wide as high. The 

 gelatinous substance is quite thick. 16 tentacles with well-developed, hollow, basal bulbs; 

 the tentacles are all of equal length and longer than the bell-diameter. Each basal bulb is 

 flanked by a pair of lateral cirri, and there are also usually 3 small thickenings upon the bell- 

 margin between each successive pair of tentacles. 8 or 12 lithocysts, 2 or 3 in each quadrant. 

 Each lithocyst contains 5 to 8 spherical concretions (see Brooks, 1886). Velum well-devel- 

 oped; 4 narrow, radial tubes. Peduncle conical, about twice as long as bell-height. Stomach 

 small, urn-shaped, 4 crenated, recurved lips. The gonads are developed upon 2 separated 

 regions on each radial-canal. They extend from near the circular vessel to near the base 

 of the peduncle and are also found upon the sides of the peduncle near its proximal end. 



The entoderm of the tentacle-bulbs and of the stomach is intense green. 



This species has been found by McCrady, 1857, and also by me in Charleston Harbor, 



